[mirror_ubuntu-jammy-kernel.git] / drivers / spi / spi_butterfly.c

/*
 * spi_butterfly.c - parport-to-butterfly adapter
 *
 * Copyright (C) 2005 David Brownell
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/parport.h>

#include <linux/spi/spi.h>
#include <linux/spi/spi_bitbang.h>
#include <linux/spi/flash.h>

#include <linux/mtd/partitions.h>


/*
 * This uses SPI to talk with an "AVR Butterfly", which is a $US20 card
 * with a battery powered AVR microcontroller and lots of goodies.  You
 * can use GCC to develop firmware for this.
 *
 * See Documentation/spi/butterfly for information about how to build
 * and use this custom parallel port cable.
 */

#undef	HAVE_USI	/* nyet */


/* DATA output bits (pins 2..9 == D0..D7) */
#define	butterfly_nreset (1 << 1)		/* pin 3 */

#define	spi_sck_bit	(1 << 0)		/* pin 2 */
#define	spi_mosi_bit	(1 << 7)		/* pin 9 */

#define	usi_sck_bit	(1 << 3)		/* pin 5 */
#define	usi_mosi_bit	(1 << 4)		/* pin 6 */

#define	vcc_bits	((1 << 6) | (1 << 5))	/* pins 7, 8 */

/* STATUS input bits */
#define	spi_miso_bit	PARPORT_STATUS_BUSY	/* pin 11 */

#define	usi_miso_bit	PARPORT_STATUS_PAPEROUT	/* pin 12 */

/* CONTROL output bits */
#define	spi_cs_bit	PARPORT_CONTROL_SELECT	/* pin 17 */
/* USI uses no chipselect */


static inline struct butterfly *spidev_to_pp(struct spi_device *spi)
{
	return spi->controller_data;
}

static inline int is_usidev(struct spi_device *spi)
{
#ifdef	HAVE_USI
	return spi->chip_select != 1;
#else
	return 0;
#endif
}


struct butterfly {
	/* REVISIT ... for now, this must be first */
	struct spi_bitbang	bitbang;

	struct parport		*port;
	struct pardevice	*pd;

	u8			lastbyte;

	struct spi_device	*dataflash;
	struct spi_device	*butterfly;
	struct spi_board_info	info[2];

};

/*----------------------------------------------------------------------*/

/*
 * these routines may be slower than necessary because they're hiding
 * the fact that there are two different SPI busses on this cable: one
 * to the DataFlash chip (or AVR SPI controller), the other to the
 * AVR USI controller.
 */

static inline void
setsck(struct spi_device *spi, int is_on)
{
	struct butterfly	*pp = spidev_to_pp(spi);
	u8			bit, byte = pp->lastbyte;

	if (is_usidev(spi))
		bit = usi_sck_bit;
	else
		bit = spi_sck_bit;

	if (is_on)
		byte |= bit;
	else
		byte &= ~bit;
	parport_write_data(pp->port, byte);
	pp->lastbyte = byte;
}

static inline void
setmosi(struct spi_device *spi, int is_on)
{
	struct butterfly	*pp = spidev_to_pp(spi);
	u8			bit, byte = pp->lastbyte;

	if (is_usidev(spi))
		bit = usi_mosi_bit;
	else
		bit = spi_mosi_bit;

	if (is_on)
		byte |= bit;
	else
		byte &= ~bit;
	parport_write_data(pp->port, byte);
	pp->lastbyte = byte;
}

static inline int getmiso(struct spi_device *spi)
{
	struct butterfly	*pp = spidev_to_pp(spi);
	int			value;
	u8			bit;

	if (is_usidev(spi))
		bit = usi_miso_bit;
	else
		bit = spi_miso_bit;

	/* only STATUS_BUSY is NOT negated */
	value = !(parport_read_status(pp->port) & bit);
	return (bit == PARPORT_STATUS_BUSY) ? value : !value;
}

static void butterfly_chipselect(struct spi_device *spi, int value)
{
	struct butterfly	*pp = spidev_to_pp(spi);

	/* set default clock polarity */
	if (value)
		setsck(spi, spi->mode & SPI_CPOL);

	/* no chipselect on this USI link config */
	if (is_usidev(spi))
		return;

	/* here, value == "activate or not" */

	/* most PARPORT_CONTROL_* bits are negated */
	if (spi_cs_bit == PARPORT_CONTROL_INIT)
		value = !value;

	/* here, value == "bit value to write in control register"  */

	parport_frob_control(pp->port, spi_cs_bit, value ? spi_cs_bit : 0);
}


/* we only needed to implement one mode here, and choose SPI_MODE_0 */

#define	spidelay(X)	do{}while(0)
//#define	spidelay	ndelay

#define	EXPAND_BITBANG_TXRX
#include <linux/spi/spi_bitbang.h>

static u32
butterfly_txrx_word_mode0(struct spi_device *spi,
		unsigned nsecs,
		u32 word, u8 bits)
{
	return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
}

/*----------------------------------------------------------------------*/

/* override default partitioning with cmdlinepart */
static struct mtd_partition partitions[] = { {
	/* JFFS2 wants partitions of 4*N blocks for this device ... */

	/* sector 0 = 8 pages * 264 bytes/page (1 block)
	 * sector 1 = 248 pages * 264 bytes/page
	 */
	.name		= "bookkeeping",	// 66 KB
	.offset		= 0,
	.size		= (8 + 248) * 264,
//	.mask_flags	= MTD_WRITEABLE,
}, {
	/* sector 2 = 256 pages * 264 bytes/page
	 * sectors 3-5 = 512 pages * 264 bytes/page
	 */
	.name		= "filesystem",		// 462 KB
	.offset		= MTDPART_OFS_APPEND,
	.size		= MTDPART_SIZ_FULL,
} };

static struct flash_platform_data flash = {
	.name		= "butterflash",
	.parts		= partitions,
	.nr_parts	= ARRAY_SIZE(partitions),
};


/* REVISIT remove this ugly global and its "only one" limitation */
static struct butterfly *butterfly;

static void butterfly_attach(struct parport *p)
{
	struct pardevice	*pd;
	int			status;
	struct butterfly	*pp;
	struct spi_master	*master;
	struct platform_device	*pdev;

	if (butterfly)
		return;

	/* REVISIT:  this just _assumes_ a butterfly is there ... no probe,
	 * and no way to be selective about what it binds to.
	 */

	/* FIXME where should master->cdev.dev come from?
	 * e.g. /sys/bus/pnp0/00:0b, some PCI thing, etc
	 * setting up a platform device like this is an ugly kluge...
	 */
	pdev = platform_device_register_simple("butterfly", -1, NULL, 0);

	master = spi_alloc_master(&pdev->dev, sizeof *pp);
	if (!master) {
		status = -ENOMEM;
		goto done;
	}
	pp = spi_master_get_devdata(master);

	/*
	 * SPI and bitbang hookup
	 *
	 * use default setup(), cleanup(), and transfer() methods; and
	 * only bother implementing mode 0.  Start it later.
	 */
	master->bus_num = 42;
	master->num_chipselect = 2;

	pp->bitbang.master = spi_master_get(master);
	pp->bitbang.chipselect = butterfly_chipselect;
	pp->bitbang.txrx_word[SPI_MODE_0] = butterfly_txrx_word_mode0;

	/*
	 * parport hookup
	 */
	pp->port = p;
	pd = parport_register_device(p, "spi_butterfly",
			NULL, NULL, NULL,
			0 /* FLAGS */, pp);
	if (!pd) {
		status = -ENOMEM;
		goto clean0;
	}
	pp->pd = pd;

	status = parport_claim(pd);
	if (status < 0)
		goto clean1;

	/*
	 * Butterfly reset, powerup, run firmware
	 */
	pr_debug("%s: powerup/reset Butterfly\n", p->name);

	/* nCS for dataflash (this bit is inverted on output) */
	parport_frob_control(pp->port, spi_cs_bit, 0);

	/* stabilize power with chip in reset (nRESET), and
	 * both spi_sck_bit and usi_sck_bit clear (CPOL=0)
	 */
	pp->lastbyte |= vcc_bits;
	parport_write_data(pp->port, pp->lastbyte);
	msleep(5);

	/* take it out of reset; assume long reset delay */
	pp->lastbyte |= butterfly_nreset;
	parport_write_data(pp->port, pp->lastbyte);
	msleep(100);


	/*
	 * Start SPI ... for now, hide that we're two physical busses.
	 */
	status = spi_bitbang_start(&pp->bitbang);
	if (status < 0)
		goto clean2;

	/* Bus 1 lets us talk to at45db041b (firmware disables AVR)
	 * or AVR (firmware resets at45, acts as spi slave)
	 */
	pp->info[0].max_speed_hz = 15 * 1000 * 1000;
	strcpy(pp->info[0].modalias, "mtd_dataflash");
	pp->info[0].platform_data = &flash;
	pp->info[0].chip_select = 1;
	pp->info[0].controller_data = pp;
	pp->dataflash = spi_new_device(pp->bitbang.master, &pp->info[0]);
	if (pp->dataflash)
		pr_debug("%s: dataflash at %s\n", p->name,
				pp->dataflash->dev.bus_id);

#ifdef	HAVE_USI
	/* even more custom AVR firmware */
	pp->info[1].max_speed_hz = 10 /* ?? */ * 1000 * 1000;
	strcpy(pp->info[1].modalias, "butterfly");
	// pp->info[1].platform_data = ... TBD ... ;
	pp->info[1].chip_select = 2,
	pp->info[1].controller_data = pp;
	pp->butterfly = spi_new_device(pp->bitbang.master, &pp->info[1]);
	if (pp->butterfly)
		pr_debug("%s: butterfly at %s\n", p->name,
				pp->butterfly->dev.bus_id);

	/* FIXME setup ACK for the IRQ line ...  */
#endif

	// dev_info(_what?_, ...)
	pr_info("%s: AVR Butterfly\n", p->name);
	butterfly = pp;
	return;

clean2:
	/* turn off VCC */
	parport_write_data(pp->port, 0);

	parport_release(pp->pd);
clean1:
	parport_unregister_device(pd);
clean0:
	(void) spi_master_put(pp->bitbang.master);
done:
	platform_device_unregister(pdev);
	pr_debug("%s: butterfly probe, fail %d\n", p->name, status);
}

static void butterfly_detach(struct parport *p)
{
	struct butterfly	*pp;
	struct platform_device	*pdev;
	int			status;

	/* FIXME this global is ugly ... but, how to quickly get from
	 * the parport to the "struct butterfly" associated with it?
	 * "old school" driver-internal device lists?
	 */
	if (!butterfly || butterfly->port != p)
		return;
	pp = butterfly;
	butterfly = NULL;

#ifdef	HAVE_USI
	spi_unregister_device(pp->butterfly);
	pp->butterfly = NULL;
#endif
	spi_unregister_device(pp->dataflash);
	pp->dataflash = NULL;

	status = spi_bitbang_stop(&pp->bitbang);

	/* turn off VCC */
	parport_write_data(pp->port, 0);
	msleep(10);

	parport_release(pp->pd);
	parport_unregister_device(pp->pd);

	pdev = to_platform_device(pp->bitbang.master->cdev.dev);

	(void) spi_master_put(pp->bitbang.master);

	platform_device_unregister(pdev);
}

static struct parport_driver butterfly_driver = {
	.name =		"spi_butterfly",
	.attach =	butterfly_attach,
	.detach =	butterfly_detach,
};


static int __init butterfly_init(void)
{
	return parport_register_driver(&butterfly_driver);
}
device_initcall(butterfly_init);

static void __exit butterfly_exit(void)
{
	parport_unregister_driver(&butterfly_driver);
}
module_exit(butterfly_exit);

MODULE_LICENSE("GPL");
Commit	Line	Data
2e10c84b DB	1	/*
	2	* spi_butterfly.c - parport-to-butterfly adapter
	3	*
	4	* Copyright (C) 2005 David Brownell
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	19	*/
	20	#include <linux/config.h>
	21	#include <linux/kernel.h>
	22	#include <linux/init.h>
	23	#include <linux/delay.h>
	24	#include <linux/platform_device.h>
	25	#include <linux/parport.h>
	26
	27	#include <linux/spi/spi.h>
	28	#include <linux/spi/spi_bitbang.h>
	29	#include <linux/spi/flash.h>
	30
	31	#include <linux/mtd/partitions.h>
	32
	33
	34	/*
	35	* This uses SPI to talk with an "AVR Butterfly", which is a $US20 card
	36	* with a battery powered AVR microcontroller and lots of goodies. You
	37	* can use GCC to develop firmware for this.
	38	*
	39	* See Documentation/spi/butterfly for information about how to build
	40	* and use this custom parallel port cable.
	41	*/
	42
	43	#undef HAVE_USI /* nyet */
	44
	45
	46	/* DATA output bits (pins 2..9 == D0..D7) */
	47	#define butterfly_nreset (1 << 1) /* pin 3 */
	48
	49	#define spi_sck_bit (1 << 0) /* pin 2 */
	50	#define spi_mosi_bit (1 << 7) /* pin 9 */
	51
	52	#define usi_sck_bit (1 << 3) /* pin 5 */
	53	#define usi_mosi_bit (1 << 4) /* pin 6 */
	54
	55	#define vcc_bits ((1 << 6) \| (1 << 5)) /* pins 7, 8 */
	56
	57	/* STATUS input bits */
	58	#define spi_miso_bit PARPORT_STATUS_BUSY /* pin 11 */
	59
	60	#define usi_miso_bit PARPORT_STATUS_PAPEROUT /* pin 12 */
	61
	62	/* CONTROL output bits */
	63	#define spi_cs_bit PARPORT_CONTROL_SELECT /* pin 17 */
	64	/* USI uses no chipselect */
65
66
67
68	static inline struct butterfly spidev_to_pp(struct spi_device spi)
69	{
70	return spi->controller_data;
71	}
72
73	static inline int is_usidev(struct spi_device *spi)
74	{
75	#ifdef HAVE_USI
76	return spi->chip_select != 1;
77	#else
78	return 0;
79	#endif
80	}
81
82
83	struct butterfly {
84	/* REVISIT ... for now, this must be first */
85	struct spi_bitbang bitbang;
86
87	struct parport *port;
88	struct pardevice *pd;
89
90	u8 lastbyte;
91
92	struct spi_device *dataflash;
93	struct spi_device *butterfly;
94	struct spi_board_info info[2];
95
96	};
97
98	/----------------------------------------------------------------------/
99
100	/*
101	* these routines may be slower than necessary because they're hiding
102	* the fact that there are two different SPI busses on this cable: one
103	* to the DataFlash chip (or AVR SPI controller), the other to the
104	* AVR USI controller.
105	*/
106
107	static inline void
108	setsck(struct spi_device *spi, int is_on)
109	{
110	struct butterfly *pp = spidev_to_pp(spi);
111	u8 bit, byte = pp->lastbyte;
112
113	if (is_usidev(spi))
114	bit = usi_sck_bit;
115	else
116	bit = spi_sck_bit;
117
118	if (is_on)
119	byte \|= bit;
120	else
121	byte &= ~bit;
122	parport_write_data(pp->port, byte);
123	pp->lastbyte = byte;
124	}
125
126	static inline void
127	setmosi(struct spi_device *spi, int is_on)
128	{
129	struct butterfly *pp = spidev_to_pp(spi);
130	u8 bit, byte = pp->lastbyte;
131
132	if (is_usidev(spi))
133	bit = usi_mosi_bit;
134	else
135	bit = spi_mosi_bit;
136
137	if (is_on)
138	byte \|= bit;
139	else
140	byte &= ~bit;
141	parport_write_data(pp->port, byte);
142	pp->lastbyte = byte;
143	}
144
145	static inline int getmiso(struct spi_device *spi)
146	{
147	struct butterfly *pp = spidev_to_pp(spi);
148	int value;
149	u8 bit;
150
151	if (is_usidev(spi))
152	bit = usi_miso_bit;
153	else
154	bit = spi_miso_bit;
155
156	/* only STATUS_BUSY is NOT negated */
157	value = !(parport_read_status(pp->port) & bit);
158	return (bit == PARPORT_STATUS_BUSY) ? value : !value;
159	}
160
161	static void butterfly_chipselect(struct spi_device *spi, int value)
162	{
163	struct butterfly *pp = spidev_to_pp(spi);
164
165	/* set default clock polarity */
166	if (value)
167	setsck(spi, spi->mode & SPI_CPOL);
168
169	/* no chipselect on this USI link config */
170	if (is_usidev(spi))
171	return;
172
173	/* here, value == "activate or not" */
174
175	/* most PARPORT_CONTROL_* bits are negated */
176	if (spi_cs_bit == PARPORT_CONTROL_INIT)
177	value = !value;
178
179	/* here, value == "bit value to write in control register" */
180
181	parport_frob_control(pp->port, spi_cs_bit, value ? spi_cs_bit : 0);
182	}
183
184
185	/* we only needed to implement one mode here, and choose SPI_MODE_0 */
186
187	#define spidelay(X) do{}while(0)
188	//#define spidelay ndelay
189
190	#define EXPAND_BITBANG_TXRX
191	#include <linux/spi/spi_bitbang.h>
192
193	static u32
194	butterfly_txrx_word_mode0(struct spi_device *spi,
195	unsigned nsecs,
196	u32 word, u8 bits)
197	{
198	return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
199	}
200
201	/----------------------------------------------------------------------/
202
203	/* override default partitioning with cmdlinepart */
204	static struct mtd_partition partitions[] = { {
205	/* JFFS2 wants partitions of 4N blocks for this device ... /
206
207	/* sector 0 = 8 pages * 264 bytes/page (1 block)
208	* sector 1 = 248 pages * 264 bytes/page
209	*/
210	.name = "bookkeeping", // 66 KB
211	.offset = 0,
212	.size = (8 + 248) * 264,
213	// .mask_flags = MTD_WRITEABLE,
214	}, {
215	/* sector 2 = 256 pages * 264 bytes/page
216	* sectors 3-5 = 512 pages * 264 bytes/page
217	*/
218	.name = "filesystem", // 462 KB
219	.offset = MTDPART_OFS_APPEND,
220	.size = MTDPART_SIZ_FULL,
221	} };
222
223	static struct flash_platform_data flash = {
224	.name = "butterflash",
225	.parts = partitions,
226	.nr_parts = ARRAY_SIZE(partitions),
227	};
228
229
230	/* REVISIT remove this ugly global and its "only one" limitation */
231	static struct butterfly *butterfly;
232
233	static void butterfly_attach(struct parport *p)
234	{
235	struct pardevice *pd;
236	int status;
237	struct butterfly *pp;
238	struct spi_master *master;
239	struct platform_device *pdev;
240
241	if (butterfly)
242	return;
243
244	/* REVISIT: this just _assumes_ a butterfly is there ... no probe,
245	* and no way to be selective about what it binds to.
246	*/
247
248	/* FIXME where should master->cdev.dev come from?
249	* e.g. /sys/bus/pnp0/00:0b, some PCI thing, etc
250	* setting up a platform device like this is an ugly kluge...
251	*/
252	pdev = platform_device_register_simple("butterfly", -1, NULL, 0);
253
254	master = spi_alloc_master(&pdev->dev, sizeof *pp);
255	if (!master) {
256	status = -ENOMEM;
257	goto done;
258	}
259	pp = spi_master_get_devdata(master);
260
261	/*
262	* SPI and bitbang hookup
263	*
264	* use default setup(), cleanup(), and transfer() methods; and
265	* only bother implementing mode 0. Start it later.
266	*/
267	master->bus_num = 42;
268	master->num_chipselect = 2;
269
270	pp->bitbang.master = spi_master_get(master);
271	pp->bitbang.chipselect = butterfly_chipselect;
272	pp->bitbang.txrx_word[SPI_MODE_0] = butterfly_txrx_word_mode0;
273
274	/*
275	* parport hookup
276	*/
277	pp->port = p;
278	pd = parport_register_device(p, "spi_butterfly",
279	NULL, NULL, NULL,
280	0 /* FLAGS */, pp);
281	if (!pd) {
282	status = -ENOMEM;
283	goto clean0;
284	}
285	pp->pd = pd;
286
287	status = parport_claim(pd);
288	if (status < 0)
289	goto clean1;
290
291	/*
292	* Butterfly reset, powerup, run firmware
293	*/
294	pr_debug("%s: powerup/reset Butterfly\n", p->name);
295
296	/* nCS for dataflash (this bit is inverted on output) */
297	parport_frob_control(pp->port, spi_cs_bit, 0);
298
299	/* stabilize power with chip in reset (nRESET), and
300	* both spi_sck_bit and usi_sck_bit clear (CPOL=0)
301	*/
302	pp->lastbyte \|= vcc_bits;
303	parport_write_data(pp->port, pp->lastbyte);
304	msleep(5);
305
306	/* take it out of reset; assume long reset delay */
307	pp->lastbyte \|= butterfly_nreset;
308	parport_write_data(pp->port, pp->lastbyte);
309	msleep(100);
310
311
312	/*
313	* Start SPI ... for now, hide that we're two physical busses.
314	*/
315	status = spi_bitbang_start(&pp->bitbang);
316	if (status < 0)
317	goto clean2;
318
319	/* Bus 1 lets us talk to at45db041b (firmware disables AVR)
320	* or AVR (firmware resets at45, acts as spi slave)
321	*/
322	pp->info[0].max_speed_hz = 15 * 1000 * 1000;
323	strcpy(pp->info[0].modalias, "mtd_dataflash");
324	pp->info[0].platform_data = &flash;
325	pp->info[0].chip_select = 1;
326	pp->info[0].controller_data = pp;
327	pp->dataflash = spi_new_device(pp->bitbang.master, &pp->info[0]);
328	if (pp->dataflash)
329	pr_debug("%s: dataflash at %s\n", p->name,
330	pp->dataflash->dev.bus_id);
331
332	#ifdef HAVE_USI
333	/* even more custom AVR firmware */
334	pp->info[1].max_speed_hz = 10 /* ?? / 1000 * 1000;
335	strcpy(pp->info[1].modalias, "butterfly");
336	// pp->info[1].platform_data = ... TBD ... ;
337	pp->info[1].chip_select = 2,
338	pp->info[1].controller_data = pp;
339	pp->butterfly = spi_new_device(pp->bitbang.master, &pp->info[1]);
340	if (pp->butterfly)
341	pr_debug("%s: butterfly at %s\n", p->name,
342	pp->butterfly->dev.bus_id);
343
344	/* FIXME setup ACK for the IRQ line ... */
345	#endif
346
347	// dev_info(_what?_, ...)
348	pr_info("%s: AVR Butterfly\n", p->name);
349	butterfly = pp;
350	return;
351
352	clean2:
353	/* turn off VCC */
354	parport_write_data(pp->port, 0);
355
356	parport_release(pp->pd);
357	clean1:
358	parport_unregister_device(pd);
359	clean0:
360	(void) spi_master_put(pp->bitbang.master);
361	done:
362	platform_device_unregister(pdev);
363	pr_debug("%s: butterfly probe, fail %d\n", p->name, status);
364	}
365
366	static void butterfly_detach(struct parport *p)
367	{
368	struct butterfly *pp;
369	struct platform_device *pdev;
370	int status;
371
372	/* FIXME this global is ugly ... but, how to quickly get from
373	* the parport to the "struct butterfly" associated with it?
374	* "old school" driver-internal device lists?
375	*/
376	if (!butterfly \|\| butterfly->port != p)
377	return;
378	pp = butterfly;
379	butterfly = NULL;
380
381	#ifdef HAVE_USI
382	spi_unregister_device(pp->butterfly);
383	pp->butterfly = NULL;
384	#endif
385	spi_unregister_device(pp->dataflash);
386	pp->dataflash = NULL;
387
388	status = spi_bitbang_stop(&pp->bitbang);
389
390	/* turn off VCC */
391	parport_write_data(pp->port, 0);
392	msleep(10);
393
394	parport_release(pp->pd);
395	parport_unregister_device(pp->pd);
396
397	pdev = to_platform_device(pp->bitbang.master->cdev.dev);
398
399	(void) spi_master_put(pp->bitbang.master);
400
401	platform_device_unregister(pdev);
402	}
403
404	static struct parport_driver butterfly_driver = {
405	.name = "spi_butterfly",
406	.attach = butterfly_attach,
407	.detach = butterfly_detach,
408	};
409
410
411	static int __init butterfly_init(void)
412	{
413	return parport_register_driver(&butterfly_driver);
414	}
415	device_initcall(butterfly_init);
416
417	static void __exit butterfly_exit(void)
418	{
419	parport_unregister_driver(&butterfly_driver);
420	}
421	module_exit(butterfly_exit);
422
423	MODULE_LICENSE("GPL");